Message type: E = Error
Message class:  RSO_SEGR - Messages for TLOGO = SEGR  (Semantic Group of ADSOs) 
Message number: 258
Message text: Could not convert '&2' of field '&1' from external to internal format
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The SAP error message RSO_SEGR258 indicates that there is an issue with converting a value from an external format to an internal format in the context of SAP BW (Business Warehouse) or SAP BI (Business Intelligence). This typically occurs when the data being processed does not match the expected format or data type defined in the system.
Cause: Data Type Mismatch: The value being processed does not conform to the expected data type for the field. For example, if a numeric field is expecting a number but receives a string or special character, this error can occur. Incorrect Formatting: The external representation of the data may not match the internal representation. This can happen with date formats, currency formats, or other localized formats. Data Quality Issues: The data being loaded or processed may contain invalid or unexpected values that cannot be converted.
Configuration Issues: There may be issues with the configuration of the InfoObject or
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